People across the globe are on the move due to environmental disruption and degradation, causing them to travel and find their future in new locations. Climate change will increase the number of people seeking to escape environmental pressures. What should be the appropriate response to this increase of migrating people, driven away from their homes as a result of climate change effects? From the perspective of normative political philosophy, it is more precise to ask two interrelated questions: what are the obligations in the context of climate change migration and to who should assign them. Previous research in normative political philosophy has focused on the high-profile case of small island states that can be submerged by the rising levels of the oceans, overlooking the wider ways in which human mobility will be induced by climate change effects. The thesis, then, fills this gap in the literature and provides a nuanced account that combines insights from political philosophy and writing on climate change and immigration. My dissertation answers the two above-mentioned questions, dedicating the first part to the ‘who’ question and taking up the ‘what’ question in the second part. The overall argument shows that states creating hazardous climate change incur obligations towards those adversely affected by it, including those relocating across international borders. And these states ought to amend or supplement their immigration policy in a way that advances the capacity of vulnerable individuals to cope with climate change. In the first part of the thesis, I establish state responsibility for the adverse effects of climate change, primarily focusing on its relation with duties towards climate change adaptation. I work with a backward-looking principle of responsibility, responsibility for causing bad outcomes, and explore its application to the case of climate change in the face of some conceptual and empirical challenges. I further develop a notion of responsibility for creating risk that can capture the collective adverse outcome states bring about by emitting greenhouse gases. I explicate the moral significance of imposing risks on others and the obligations that it gives rise to. Building on this theoretical groundwork, the second part of the thesis dives into the complex nexus of climate change and human mobility. I focus on a particular pattern of immigrationinternational movement due to gradual environmental changes associated with climate change that significantly restrict people’s life prospects. I defend a view that perceives such migratory scenarios as a way to cope with climate change, a form of adaptation. I argue that the obligations of states include providing admission to climate immigrants. However, they are part of a wider set of actions and policies to advance the adaptation capacity of all individuals vulnerable to climate change hazards: immigrants themselves, but also the immobile. This part of thesis shows that the adaptation duty of states is a complex balancing act between providing admission and supporting local adaptation. The last chapter elaborates on this challenge. Drawing on the research on climate immigration, I highlight the aspects of this movement that must be considered in a morally informed immigration policy. In addition, I put forward the possibility that states can allocate among themselves their obligations so some will do more in terms of admitting immigrants and some will do more in terms of supporting local adaptation.